The invention relates generally to monitoring systems for electromagnetic launcher axial components, and more particularly to such configurations that preferably can provide continuous condition measurements of launcher barrels from launching a projectile at high speed. Such conditions for measuring include dynamic deformation, temperature, strain and humidity.
An electromagnetic launcher (e.g., barrel accelerator) utilizes electromagnetic force to propel an electrically conductive payload. Electrically conductive rails may be disposed in a longitudinal launch direction from breech to muzzle ends of the launcher. Electric current flowing through the rails induces a magnetic field that produces a mutual repulsion Lorenz force between the rails and accelerates the payload (armature and projectile) along at least one of the rails. The armature pushes the projectile for release through the muzzle.
Laboratory railguns have demonstrated launch velocities of over 2 km/s, considerably above those normally achieved in conventional propellant guns. Such velocities enable both increased range and elimination of energetic materials for propulsion. Physical and design constraints limit launch speeds and rail performance after firing multiple loads without structural or operational failure, which often necessitates post-mortem investigation of system fragments that have suffered damage from the intended operation.
Experiments with various high-speed accelerators reveal existence of critical speeds causing group resonance with significant localized bending and buckling in barrels. These result in high tensile stress, creation of gouges, pits and cracks along rails, delamination of insulators, possible arc generation with high localized temperatures.